Foundry Fund Me

This is a learning project focussed on Smart Contract development & testing with Foundry.

• Foundry Fund Me
• Getting Started
  • Requirements
  • Quickstart
• Usage
  • Testing
    • Test Coverage
• Deployment to a testnet or mainnet
  • Scripts
    • Withdraw
  • Estimate gas
• Formatting

Getting Started

Requirements

• git
  • You'll know you did it right if you can run git --version and you see a response like git version x.x.x
• foundry
  • You'll know you did it right if you can run forge --version and you see a response like forge 0.2.0 (816e00b 2023-03-16T00:05:26.396218Z)

Quickstart

git clone https://github.com/shobhit-gupta/blockchain-foundry-fundme.git
cd blockchain-foundry-fundme
forge build

Usage

Deploy:

forge script scripts/DeployFundMe.s.sol

Testing

For now, the focus is on 2 types of testing here:

1. Unit
2. Forked

forge test

or

// Only run test functions matching the specified regex pattern.
forge test --match-test testFunctionName

// You can also use the shorthand --mt instead of --match-test

or

forge test --fork-url $SEPOLIA_RPC_URL

Test Coverage

forge coverage

Deployment to a testnet or mainnet

1. Setup environment variables

You'll want to set your SEPOLIA_RPC_URL and PRIVATE_KEY as environment variables. You can add them to a .env file, similar to what you see in .env.example.

• PRIVATE_KEY: The private key of your account (like from metamask). NOTE: FOR DEVELOPMENT, PLEASE USE A KEY THAT DOESN'T HAVE ANY REAL FUNDS ASSOCIATED WITH IT.
  • You can learn how to export it here.
• SEPOLIA_RPC_URL: This is url of the sepolia testnet node you're working with. You can get setup with one for free from Alchemy

Optionally, add your ETHERSCAN_API_KEY if you want to verify your contract on Etherscan.

1. Get testnet ETH

Head over to faucets.chain.link and get some testnet ETH. You should see the ETH show up in your metamask.

3. Deploy

forge script script/DeployFundMe.s.sol --rpc-url $SEPOLIA_RPC_URL --private-key $PRIVATE_KEY --broadcast --verify --etherscan-api-key $ETHERSCAN_API_KEY

Scripts

After deploying to a testnet or local net, you can run the scripts.

Using cast deployed locally example:

cast send <FUNDME_CONTRACT_ADDRESS> "fund()" --value 0.1ether --private-key <PRIVATE_KEY>

or

forge script script/FundFundMe.s.sol --rpc-url sepolia  --private-key $PRIVATE_KEY  --broadcast

Withdraw

cast send <FUNDME_CONTRACT_ADDRESS> "withdraw()"  --private-key <PRIVATE_KEY>

Estimate gas

You can estimate how much gas things cost by running:

forge snapshot

And you'll see an output file called .gas-snapshot

Formatting

To run code formatting:

forge fmt